diff --git a/apps/api/src/routes/submission-statistics.ts b/apps/api/src/routes/submission-statistics.ts
index c575f7c..ef9820a 100644
--- a/apps/api/src/routes/submission-statistics.ts
+++ b/apps/api/src/routes/submission-statistics.ts
@@ -7,6 +7,7 @@
  */
 
 import {
+  type ProblemLanguage,
   type SubmissionStatistics,
   type SubmissionStatisticsGrid,
   type TodaySubmissionStatistics,
@@ -17,111 +18,226 @@ import { Hono } from "hono"
 import { optionalAuth, requireTeacher } from "../auth/middleware"
 import { db, schema } from "../db"
 import { failure, success } from "../http"
-import { JudgeStatus, UNJUDGED_RESULTS } from "../judge/status"
+import { JudgeStatus, UNJUDGED_RESULTS, type JudgeStatusValue } from "../judge/status"
 import { type ContestEnv } from "../services/contest"
 import { getBooleanOption } from "../services/options"
-import { localTime, dayStart } from "../time"
-import { isAdminRole, parseDisplayIds, rounded, scopedUsers, stripClassPrefix } from "./helpers"
+import { dayStart } from "../time"
+import {
+  isAdminRole,
+  isTeacherOrAbove,
+  parseDisplayIds,
+  rounded,
+  scopedUsers,
+  stripClassPrefix,
+} from "./helpers"
 
 export const submissionStatisticsRoutes = new Hono<ContestEnv>()
 
-const ACCEPTED_RESULTS = [JudgeStatus.ACCEPTED, JudgeStatus.AST_CHECK_FAILED]
+const ACCEPTED_RESULTS: JudgeStatusValue[] = [JudgeStatus.ACCEPTED, JudgeStatus.AST_CHECK_FAILED]
 
 /** 正确率。分母是判完的条数，一条都还没判完时给 0 而不是 NaN */
 function judgedRate(accepted: number, judged: number) {
   return judged > 0 ? rounded((accepted / judged) * 100) : 0
 }
 
+/** 同班这么多人做了同一道题，才算这个班今天上了课（和首页「班里在做」同一个门槛） */
+const TODAY_LESSON_MIN_USERS = 5
+/** 最后一条提交在这么多分钟内，算「正在上课」 */
+const TODAY_LIVE_MINUTES = 15
+
+type TodayRow = {
+  class_name: string | null
+  problem_id: number
+  display_id: string
+  title: string
+  visible: boolean
+  problemset_id: number | null
+  user_id: number
+  result: JudgeStatusValue
+  language: ProblemLanguage
+  create_time: string
+}
+
 /**
- * 「今日提交数」标签点开的统计。**公开、只出聚合数**（没有用户名、没有代码，
- * 热门题只算公开可见的题），口径和那颗标签一致：东八区今天 + 非比赛提交。
+ * 「今日统计」（提交列表顶上那颗标签点开的）。一般是老师看：今天哪几个班上了课、几点到几点、
+ * 错得最多的是哪几道；学生版从简。口径和那颗标签一致：东八区今天 + 非比赛提交。
  *
- * 按钟点切用 `localTime()`，不能写 `extract(hour from create_time)` ——
- * 后者按数据库会话时区算，容器是 UTC，整张分布图会整体左移 8 小时。
+ * 今天的提交一天也就几百到一千来条，整批拉回来在进程里分组，比写五六条各自 group by 的
+ * SQL 好读，也只扫一遍 `create_time` 索引。
  */
 submissionStatisticsRoutes.get("/submissions/today-statistics", optionalAuth, async (c) => {
+  const user = c.get("user")
   /**
-   * 「提交列表对学生全开」关掉时（考试那种场合）不给热门题这张表 —— 总数、正确率
+   * 「提交列表对学生全开」关掉时（考试那种场合）不给题目这张表 —— 总数、正确率
    * 这些聚合数原本就从公开的 today-count 看得出来，但「哪几道题在被刷」已经贴近
    * 提交列表本身的内容了，得跟着同一个开关走。数字照给，不然标签说 21、弹框说 0。
    */
   const showProblems =
-    (await getBooleanOption("submission_list_show_all", true)) || isAdminRole(c.get("user"))
-  const where = and(
-    isNull(schema.submission.contestId),
-    sql`${schema.submission.createTime} >= ${dayStart()}`,
-  )
-  const acceptedFilter = sql`count(*) filter (where ${inArray(schema.submission.result, ACCEPTED_RESULTS)})`
-  const judgingFilter = sql`count(*) filter (where ${inArray(schema.submission.result, UNJUDGED_RESULTS)})`
-  const hour = sql<number>`extract(hour from ${localTime(schema.submission.createTime)})::int`
-
-  const [[totals], hourRows, languageRows, resultRows, problemRows] = await Promise.all([
+    (await getBooleanOption("submission_list_show_all", true)) || isAdminRole(user)
+  const teacher = isTeacherOrAbove(user)
+  const since = dayStart()
+  const [rows, [flow]] = await Promise.all([
+    db.execute<TodayRow>(sql`
+      select u.class_name, s.problem_id, p._id as display_id, p.title, p.visible,
+        s.problemset_id, s.user_id, s.result, s.language, s.create_time
+      from ${schema.submission} s
+      join ${schema.problem} p on p.id = s.problem_id
+      left join ${schema.user} u on u.id = s.user_id
+      where s.contest_id is null and s.create_time >= ${since}
+    `),
     db
-      .select({
-        total: count(),
-        accepted: acceptedFilter.mapWith(Number),
-        judging: judgingFilter.mapWith(Number),
-        userCount: sql<number>`count(distinct ${schema.submission.userId})`.mapWith(Number),
-      })
-      .from(schema.submission)
-      .where(where),
-    db.select({ hour, value: count() }).from(schema.submission).where(where).groupBy(hour),
-    db
-      .select({ language: schema.submission.language, value: count() })
-      .from(schema.submission)
-      .where(where)
-      .groupBy(schema.submission.language)
-      .orderBy(desc(count())),
-    db
-      .select({ result: schema.submission.result, value: count() })
-      .from(schema.submission)
-      .where(where)
-      .groupBy(schema.submission.result)
-      .orderBy(desc(count())),
-    showProblems
-      ? db
-          .select({
-            displayId: schema.problem.displayId,
-            title: schema.problem.title,
-            value: count(),
-            accepted: acceptedFilter.mapWith(Number),
-          })
-          .from(schema.submission)
-          .innerJoin(schema.problem, eq(schema.problem.id, schema.submission.problemId))
-          // 隐藏题目不出现在这张表里：接口不需要登录，标题本身就是不该外露的东西
-          .where(and(where, eq(schema.problem.visible, true)))
-          .groupBy(schema.problem.id, schema.problem.displayId, schema.problem.title)
-          .orderBy(desc(count()))
-          .limit(10)
-      : [],
+      .select({ value: count() })
+      .from(schema.flowchartSubmission)
+      .where(sql`${schema.flowchartSubmission.createTime} >= ${since}`),
   ])
 
-  const total = totals?.total ?? 0
-  const judging = totals?.judging ?? 0
-  const hours = Array.from({ length: 24 }, () => 0)
-  for (const row of hourRows) hours[row.hour] = row.value
+  const isAccepted = (row: TodayRow) => ACCEPTED_RESULTS.includes(row.result)
+  const isJudging = (row: TodayRow) => UNJUDGED_RESULTS.includes(row.result)
+  const rate = (list: TodayRow[]) => {
+    const judging = list.filter(isJudging).length
+    return judgedRate(list.filter(isAccepted).length, list.length - judging)
+  }
+  const distinctUsers = (list: TodayRow[]) => new Set(list.map((row) => row.user_id)).size
+  const acceptedUsers = (list: TodayRow[]) =>
+    new Set(list.filter(isAccepted).map((row) => row.user_id)).size
+  const groupBy = <K>(list: TodayRow[], key: (row: TodayRow) => K) => {
+    const map = new Map<K, TodayRow[]>()
+    for (const row of list) map.set(key(row), [...(map.get(key(row)) ?? []), row])
+    return map
+  }
+  const countBy = <K>(list: TodayRow[], key: (row: TodayRow) => K) =>
+    [...groupBy(list, key)]
+      .map(([value, group]) => ({ value, count: group.length }))
+      .sort((a, b) => b.count - a.count)
+
+  const judging = rows.filter(isJudging).length
+  const byProblem = groupBy(rows, (row) => row.problem_id)
+  const mineRows = user ? rows.filter((row) => row.user_id === user.id) : []
+
+  // ---------- 学生：大家都在做 ----------
+  const problems = showProblems
+    ? [...byProblem.values()]
+        .filter((list) => list[0]!.visible)
+        .map((list) => {
+          const mine = user ? list.filter((row) => row.user_id === user.id) : []
+          return {
+            problemDisplayId: list[0]!.display_id,
+            problemTitle: list[0]!.title,
+            userCount: distinctUsers(list),
+            acceptedUsers: acceptedUsers(list),
+            mine: !user
+              ? null
+              : mine.some(isAccepted)
+                ? ("accepted" as const)
+                : mine.length
+                  ? ("tried" as const)
+                  : ("none" as const),
+          }
+        })
+        .sort((a, b) => b.userCount - a.userCount)
+        .slice(0, 8)
+    : []
+
+  // ---------- 老师：哪几个班上了课、错得最多的题 ----------
+  let classes: TodaySubmissionStatistics["classes"] = null
+  let scattered: TodaySubmissionStatistics["scattered"] = null
+  let hardProblems: TodaySubmissionStatistics["hardProblems"] = null
+  if (teacher) {
+    const byClass = groupBy(rows, (row) => row.class_name)
+    const lessonClasses: { className: string; list: TodayRow[]; problemCount: number }[] = []
+    scattered = []
+    for (const [className, list] of byClass) {
+      const problemCount = className
+        ? [...groupBy(list, (row) => row.problem_id).values()].filter(
+            (group) => distinctUsers(group) >= TODAY_LESSON_MIN_USERS,
+          ).length
+        : 0
+      if (className && problemCount) lessonClasses.push({ className, list, problemCount })
+      else scattered.push({ className, userCount: distinctUsers(list), total: list.length })
+    }
+    scattered.sort((a, b) =>
+      a.className === null ? 1 : b.className === null ? -1 : b.total - a.total,
+    )
+    const sizes = lessonClasses.length
+      ? await db
+          .select({ className: schema.user.className, value: count() })
+          .from(schema.user)
+          .where(
+            and(
+              inArray(
+                schema.user.className,
+                lessonClasses.map((item) => item.className),
+              ),
+              eq(schema.user.adminType, "Regular User"),
+              eq(schema.user.isDisabled, false),
+            ),
+          )
+          .groupBy(schema.user.className)
+      : []
+    const liveSince = new Date(Date.now() - TODAY_LIVE_MINUTES * 60_000).toISOString()
+    classes = lessonClasses
+      .map(({ className, list, problemCount }) => {
+        const times = list.map((row) => row.create_time).sort()
+        return {
+          className,
+          start: times[0]!,
+          end: times.at(-1)!,
+          userCount: distinctUsers(list),
+          classSize: sizes.find((row) => row.className === className)?.value ?? 0,
+          problemCount,
+          fromProblemSet: list.filter((row) => row.problemset_id !== null).length * 2 > list.length,
+          total: list.length,
+          correctRate: rate(list),
+          live: times.at(-1)! >= liveSince,
+        }
+      })
+      .sort((a, b) => a.start.localeCompare(b.start))
+    const failedOf = (list: TodayRow[]) => list.filter((row) => !isAccepted(row) && !isJudging(row))
+    hardProblems = [...byProblem.values()]
+      .filter((list) => failedOf(list).length > 0)
+      .sort((a, b) => failedOf(b).length - failedOf(a).length)
+      .slice(0, 6)
+      .map((list) => ({
+        problemDisplayId: list[0]!.display_id,
+        problemTitle: list[0]!.title,
+        className: countBy(list, (row) => row.class_name)[0]?.value ?? null,
+        total: list.length,
+        accepted: list.filter(isAccepted).length,
+        failures: countBy(failedOf(list), (row) => row.result).map(({ value, count }) => ({
+          result: value,
+          count,
+        })),
+        userCount: distinctUsers(list),
+        acceptedUsers: acceptedUsers(list),
+      }))
+  }
 
   return success(c, {
-    total,
-    accepted: totals?.accepted ?? 0,
+    asOf: new Date().toISOString(),
+    total: rows.length,
+    accepted: rows.filter(isAccepted).length,
     judging,
-    correctRate: judgedRate(totals?.accepted ?? 0, total - judging),
-    userCount: totals?.userCount ?? 0,
-    hours,
-    languages: languageRows.map((row) => ({
-      language: row.language,
-      count: row.value,
+    correctRate: rate(rows),
+    userCount: distinctUsers(rows),
+    flowchartCount: flow?.value ?? 0,
+    languages: countBy(rows, (row) => row.language).map(({ value, count }) => ({
+      language: value,
+      count,
     })),
-    results: resultRows.map((row) => ({
-      result: row.result,
-      count: row.value,
-    })),
-    problems: problemRows.map((row) => ({
-      problemDisplayId: row.displayId,
-      problemTitle: row.title,
-      count: row.value,
-      acceptedCount: row.accepted,
+    results: countBy(rows, (row) => row.result).map(({ value, count }) => ({
+      result: value,
+      count,
     })),
+    me: user
+      ? {
+          total: mineRows.length,
+          solved: new Set(mineRows.filter(isAccepted).map((row) => row.problem_id)).size,
+        }
+      : null,
+    problems,
+    classes,
+    scattered,
+    hardProblems,
   } satisfies TodaySubmissionStatistics)
 })
 
diff --git a/apps/web/src/oj/submission/components/TodayStatistics.vue b/apps/web/src/oj/submission/components/TodayStatistics.vue
index 137bd02..785b8fc 100644
--- a/apps/web/src/oj/submission/components/TodayStatistics.vue
+++ b/apps/web/src/oj/submission/components/TodayStatistics.vue
@@ -1,240 +1,771 @@
 <script setup lang="ts">
+import { Icon } from "@iconify/vue"
 import { useThemeVars } from "naive-ui"
 import { getTodaySubmissionStatistics } from "oj/api"
-import { LANGUAGE_SHOW_VALUE } from "utils/constants"
-import { zonedParts } from "utils/functions"
-import SubmissionResultTag from "shared/components/SubmissionResultTag.vue"
-import type { TodaySubmissionStatistics } from "@oj2/contract"
+import { JUDGE_STATUS, LANGUAGE_SHOW_VALUE } from "utils/constants"
+import { parseTime, zonedParts } from "utils/functions"
+import type { SUBMISSION_RESULT, TodaySubmissionStatistics } from "utils/types"
+import { useTone, type Tone } from "../composables/tone"
+import { classLabel } from "../utils"
 
-const emit = defineEmits<{ openProblem: [problem: string] }>()
+/**
+ * 今日统计（设计稿「今日统计重设计」）。一般是老师在看：今天哪几个班上了课、几点到几点、
+ * 错得最多的是哪几道（老师 B）。学生版从简：自己今天怎样、大家在做哪几道。
+ * 盯人、实时刷新是课堂看板的活，这里不做；有班正在上课时直接引过去。
+ */
+const emit = defineEmits<{
+  close: []
+  openProblem: [problem: string]
+  /** 拉到数之后把总数报回去：按钮上的数只在进页面时拉过一次，停久了会对不上 */
+  loaded: [total: number]
+}>()
 
-const themeVars = useThemeVars()
+const router = useRouter()
+const theme = useThemeVars()
+const tone = useTone()
 
 const stats = ref<TodaySubmissionStatistics | null>(null)
-const loading = ref(true)
-
-// 柱子高度用的像素上限。CSS 里 .hour-bars 的高度跟着它
-const BAR_MAX_HEIGHT = 72
-
-// 「现在是几点」按东八区取，不跟浏览器时区走 —— 高亮错一格比不高亮更糟
-const currentHour = zonedParts(new Date())!.hour
-
-const maxHour = computed(() => Math.max(1, ...(stats.value?.hours ?? [])))
-const maxLanguage = computed(() =>
-  Math.max(1, ...(stats.value?.languages ?? []).map((row) => row.count)),
-)
-
-/** 0 条的钟点不画柱子，横轴那条基线本身就代表「这个钟点没人交」 */
-function barHeight(value: number) {
-  if (value <= 0) return "0px"
-  return `${Math.max(4, Math.round((value / maxHour.value) * BAR_MAX_HEIGHT))}px`
-}
+const failed = ref(false)
 
 onMounted(async () => {
   try {
     stats.value = await getTodaySubmissionStatistics()
-  } finally {
-    loading.value = false
+    emit("loaded", stats.value.total)
+  } catch {
+    failed.value = true
   }
 })
+
+const teacher = computed(() => stats.value?.classes != null)
+
+const WEEKDAYS = ["周日", "周一", "周二", "周三", "周四", "周五", "周六"]
+
+const headText = computed(() => {
+  const at = stats.value?.asOf ?? new Date().toISOString()
+  const p = zonedParts(at)!
+  const weekday = WEEKDAYS[new Date(Date.UTC(p.year, p.month - 1, p.day)).getUTCDay()]
+  return `${p.month}月${p.day}日 ${weekday} · 截至 ${parseTime(at, "HH:mm")}`
+})
+
+function resultName(result: number) {
+  return JUDGE_STATUS[result as SUBMISSION_RESULT]?.name ?? "其他"
+}
+
+/** 结果条的颜色：答案正确绿、运行时错误橙、答案错误红、编译失败和判题中灰 */
+function resultColor(result: number) {
+  if (result === -2) return theme.value.textColor3
+  // 等待评分 / 判题中：还没有结果，不该和运行时错误一样是橙色
+  if (result === 6 || result === 7) return theme.value.borderColor
+  const kind: Tone = JUDGE_STATUS[result as SUBMISSION_RESULT]?.type ?? "default"
+  if (kind !== "success" && kind !== "error" && kind !== "warning") return theme.value.borderColor
+  return tone(kind).color
+}
+
+function percent(value: number, total: number) {
+  return total ? `${(value / total) * 100}%` : "0"
+}
+
+// ---------- 老师：各班时间轴 ----------
+
+/** 东八区的「几点几分」换成小时的小数，给时间轴定位 */
+function hourOf(value: string) {
+  const p = zonedParts(value)!
+  return p.hour + p.minute / 60
+}
+
+/** 横轴默认 7 点到 20 点（机房上课的时段），有更早更晚的提交就往外扩 */
+const axis = computed(() => {
+  const list = stats.value?.classes ?? []
+  const start = Math.min(7, ...list.map((item) => Math.floor(hourOf(item.start))))
+  const end = Math.max(20, ...list.map((item) => Math.ceil(hourOf(item.end))))
+  return { start, end, ticks: Array.from({ length: end - start + 1 }, (_, i) => start + i) }
+})
+
+function axisLeft(hour: number) {
+  const { start, end } = axis.value
+  return `${((hour - start) / (end - start)) * 100}%`
+}
+
+function barStyle(item: { start: string; end: string; live: boolean }) {
+  const from = hourOf(item.start)
+  const to = hourOf(item.end)
+  const { start, end } = axis.value
+  return {
+    left: axisLeft(from),
+    width: `max(8px, ${((to - from) / (end - start)) * 100}%)`,
+    background: item.live ? theme.value.successColor : "#3f5f87",
+  }
+}
+
+/** 横条靠近右边时文字放到条的左边，不然「497 次 · 正确率 31%」被弹框右边裁掉 */
+function textStyle(item: { start: string; end: string }) {
+  const { start, end } = axis.value
+  if ((hourOf(item.end) - start) / (end - start) > 0.72) {
+    return { right: `calc(100% - ${axisLeft(hourOf(item.start))} + 10px)` }
+  }
+  return { left: `calc(${axisLeft(hourOf(item.end))} + 14px)` }
+}
+
+const nowHour = computed(() => {
+  const at = stats.value?.asOf
+  if (!at) return null
+  const hour = hourOf(at)
+  return hour >= axis.value.start && hour <= axis.value.end ? hour : null
+})
+
+const liveClasses = computed(() => (stats.value?.classes ?? []).filter((item) => item.live))
+
+/** 23 人来了、花名册却只有 22（有个号不是学生角色）时，不写「23 / 22」 */
+function attendance(item: { userCount: number; classSize: number }) {
+  return item.classSize >= item.userCount
+    ? `${item.userCount} / ${item.classSize} 人`
+    : `${item.userCount} 人`
+}
+
+const scatteredText = computed(() =>
+  (stats.value?.scattered ?? [])
+    .map(
+      (item) =>
+        `${item.className ? classLabel(item.className) : "没填班级的"} ${item.userCount} 人 ${item.total} 次`,
+    )
+    .join("、"),
+)
+
+function openClass(className: string) {
+  const href = router.resolve({
+    name: "statistics",
+    query: { className, period: "today" },
+  }).href
+  window.open(href, "_blank")
+}
+
+const judgedResults = computed(() => stats.value?.results ?? [])
+
+const languageText = computed(() => {
+  const list = stats.value?.languages ?? []
+  if (!list.length) return ""
+  if (list.length === 1) return `语言：全部是 ${LANGUAGE_SHOW_VALUE[list[0]!.language]}`
+  return `语言：${list.map((item) => `${LANGUAGE_SHOW_VALUE[item.language]} ${item.count}`).join(" · ")}`
+})
+
+// ---------- 学生 ----------
+
+const meText = computed(() => {
+  const me = stats.value?.me
+  if (!me) return ""
+  return me.total ? `交了 ${me.total} 次，做对 ${me.solved} 道` : "还没交过"
+})
 </script>
 
 <template>
-  <n-spin :show="loading">
-    <n-empty
-      v-if="stats && stats.total === 0"
-      description="今天还没有人提交"
-      style="margin: 40px 0"
-    />
-    <template v-else-if="stats">
-      <n-flex justify="space-around">
-        <div class="stat-item">
-          <n-text>总提交</n-text>
-          <n-gradient-text type="info" font-size="28">
-            {{ stats.total }}
-          </n-gradient-text>
-        </div>
-        <div class="stat-item">
-          <n-text>正确提交</n-text>
-          <n-gradient-text type="primary" font-size="28">
-            {{ stats.accepted }}
-          </n-gradient-text>
-        </div>
-        <div class="stat-item" v-if="stats.judging > 0">
-          <n-text>判题中</n-text>
-          <n-gradient-text type="info" font-size="28">
-            {{ stats.judging }}
-          </n-gradient-text>
-        </div>
-        <div class="stat-item">
-          <n-text>正确率</n-text>
-          <n-gradient-text type="warning" font-size="28">
-            {{ stats.correctRate }}%
-          </n-gradient-text>
-        </div>
-        <div class="stat-item">
-          <n-text>参与人数</n-text>
-          <n-gradient-text type="error" font-size="28">
-            {{ stats.userCount }}
-          </n-gradient-text>
-        </div>
-      </n-flex>
+  <div class="today" :class="{ wide: teacher }">
+    <div class="head">
+      <b class="title">今日统计</b>
+      <n-text depth="3" class="small">{{ headText }}</n-text>
+      <span v-if="stats?.judging" class="pill">判题中 {{ stats.judging }}</span>
+      <span class="spacer"></span>
+      <button type="button" class="close" aria-label="关闭" @click="emit('close')">
+        <Icon icon="ph:x" :width="18" />
+      </button>
+    </div>
 
-      <n-divider style="margin: 16px 0">按小时</n-divider>
-      <div class="hours">
-        <div class="hour" v-for="(value, hour) in stats.hours" :key="hour">
-          <n-tooltip>
-            <template #trigger>
-              <!--
-                基线是每一格自己的下边框拼出来的（整条横轴一根 border 也行，但那样
-                「现在」这一格就没法单独加粗）。**现在这一格加粗成主色**，
-                原来是给整格垫一层底色，结果那块浅灰看着就像一根柱子。
-              -->
-              <div
-                class="hour-bars"
-                :style="{
-                  borderBottomColor:
-                    hour === currentHour ? themeVars.primaryColor : themeVars.dividerColor,
-                }"
-              >
-                <div
-                  class="bar"
-                  :style="{
-                    height: barHeight(value),
-                    backgroundColor: themeVars.primaryColor,
-                  }"
-                ></div>
-              </div>
-            </template>
-            {{ hour }}:00 - {{ hour }}:59 共 {{ value }} 条
-          </n-tooltip>
-          <!-- 每 3 小时标一个刻度。标签占位始终留着，柱子才对得齐 -->
-          <div class="hour-label">{{ hour % 3 === 0 ? hour : "" }}</div>
-        </div>
+    <div class="body">
+      <n-text v-if="failed" type="error">统计没拉下来，关掉再打开试试</n-text>
+      <div v-else-if="!stats" class="center"><n-spin size="small" /></div>
+
+      <div v-else-if="!stats.total" class="empty">
+        <span class="empty-icon"><Icon icon="ph:chart-bar" :width="20" /></span>
+        <b>今天还没有人交</b>
+        <n-text depth="3">第一条提交进来之后这里就有数了</n-text>
       </div>
 
-      <n-divider style="margin: 16px 0">按语言</n-divider>
-      <div class="rows">
-        <div class="row" v-for="row in stats.languages" :key="row.language">
-          <n-text class="row-name">{{ LANGUAGE_SHOW_VALUE[row.language] }}</n-text>
-          <n-progress
-            class="row-bar"
-            type="line"
-            :percentage="(row.count / maxLanguage) * 100"
-            :show-indicator="false"
-            :height="10"
-          />
-          <n-text class="row-count">{{ row.count }}</n-text>
-        </div>
-      </div>
-
-      <n-divider style="margin: 16px 0">按状态</n-divider>
-      <n-flex align="center">
-        <n-flex align="center" :size="4" v-for="row in stats.results" :key="row.result">
-          <SubmissionResultTag :result="row.result" />
-          <n-text>{{ row.count }}</n-text>
-        </n-flex>
-      </n-flex>
-
-      <template v-if="stats.problems.length">
-        <n-divider style="margin: 16px 0">今天最热的题</n-divider>
-        <div class="rows">
-          <div class="row" v-for="row in stats.problems" :key="row.problemDisplayId">
-            <n-button
-              class="problem"
-              text
-              type="info"
-              @click="emit('openProblem', row.problemDisplayId)"
-            >
-              {{ row.problemDisplayId }} {{ row.problemTitle }}
-            </n-button>
-            <n-text class="row-count" depth="3">
-              {{ row.count }} 条 / 正确 {{ row.acceptedCount }}
-            </n-text>
+      <!-- ==================== 老师 ==================== -->
+      <template v-else-if="teacher">
+        <div class="numbers">
+          <div>
+            <b>{{ stats.total }}</b
+            ><span>次提交</span>
+          </div>
+          <div>
+            <b>{{ stats.userCount }}</b
+            ><span>人</span>
+          </div>
+          <div>
+            <b>{{ stats.correctRate }}%</b><span>提交正确率</span>
+          </div>
+          <div>
+            <b>{{ stats.classes!.length }}</b
+            ><span>个班上了课</span>
           </div>
         </div>
+
+        <div
+          v-if="liveClasses.length"
+          class="live"
+          :style="{ background: tone('success').background, color: tone('success').color }"
+        >
+          <span>
+            {{ liveClasses.map((item) => classLabel(item.className)).join("、") }}正在上课
+          </span>
+          <span class="spacer"></span>
+          <a href="#" class="live-link" @click.prevent="router.push('/classroom')">
+            <Icon icon="ph:monitor" :width="14" />去课堂看板
+          </a>
+        </div>
+
+        <template v-if="stats.classes!.length">
+          <div class="section-title">
+            <b>今天哪几个班上了课</b>
+            <n-text depth="3" class="small">点班级名去数据统计看今天</n-text>
+          </div>
+          <div class="timeline">
+            <div v-for="item in stats.classes" :key="item.className" class="lane">
+              <div class="lane-label">
+                <a href="#" class="lane-name" @click.prevent="openClass(item.className)">
+                  {{ classLabel(item.className) }}
+                </a>
+                <n-text depth="3" class="tiny">
+                  {{ attendance(item) }} · {{ item.fromProblemSet ? "题单" : ""
+                  }}{{ item.problemCount }} 道题
+                </n-text>
+              </div>
+              <div class="lane-track">
+                <span
+                  v-for="tick in axis.ticks"
+                  :key="tick"
+                  class="grid"
+                  :style="{ left: axisLeft(tick) }"
+                ></span>
+                <span class="lane-bar" :style="barStyle(item)"></span>
+                <span class="lane-text" :style="textStyle(item)">
+                  {{ item.total }} 次 ·
+                  {{ item.live ? "上课中" : `正确率 ${Math.round(item.correctRate)}%` }}
+                </span>
+                <span
+                  v-if="nowHour !== null"
+                  class="now"
+                  :style="{ left: axisLeft(nowHour) }"
+                ></span>
+              </div>
+            </div>
+            <div class="lane axis-row">
+              <div class="lane-label"></div>
+              <div class="lane-track axis">
+                <span v-for="tick in axis.ticks" :key="tick" :style="{ left: axisLeft(tick) }">
+                  {{ tick }}
+                </span>
+                <span
+                  v-if="nowHour !== null"
+                  class="now-label"
+                  :style="{ left: axisLeft(nowHour) }"
+                >
+                  现在
+                </span>
+              </div>
+            </div>
+          </div>
+        </template>
+        <n-text v-if="scatteredText" depth="3" class="small">
+          {{ stats.classes!.length ? "另有零散提交：" : "今天没有哪个班一起上课，零散提交："
+          }}{{ scatteredText }}
+        </n-text>
+
+        <template v-if="stats.hardProblems?.length">
+          <div class="section-title">
+            <b>错得最多的题</b>
+            <n-text depth="3" class="small">按没过的次数</n-text>
+          </div>
+          <table class="hard">
+            <thead>
+              <tr>
+                <th>题目</th>
+                <th>哪个班</th>
+                <th>提交</th>
+                <th>没过的原因</th>
+                <th class="right">做对</th>
+              </tr>
+            </thead>
+            <tbody>
+              <tr v-for="item in stats.hardProblems" :key="item.problemDisplayId">
+                <td class="hard-title">
+                  <a href="#" @click.prevent="emit('openProblem', item.problemDisplayId)">
+                    <n-text depth="3">{{ item.problemDisplayId }}</n-text> {{ item.problemTitle }}
+                  </a>
+                </td>
+                <td>
+                  <n-text depth="2">{{ item.className ? classLabel(item.className) : "—" }}</n-text>
+                </td>
+                <td>{{ item.total }} 次</td>
+                <td>
+                  <span class="mini">
+                    <span
+                      :style="{
+                        width: percent(item.accepted, item.total),
+                        background: resultColor(0),
+                      }"
+                    ></span>
+                    <span
+                      v-for="fail in item.failures"
+                      :key="fail.result"
+                      :style="{
+                        width: percent(fail.count, item.total),
+                        background: resultColor(fail.result),
+                      }"
+                    ></span>
+                  </span>
+                  <n-text depth="2" class="small">
+                    {{ resultName(item.failures[0]!.result) }} {{ item.failures[0]!.count }}
+                  </n-text>
+                </td>
+                <td
+                  class="right"
+                  :style="{
+                    color: item.acceptedUsers < item.userCount ? tone('error').color : undefined,
+                    fontWeight: item.acceptedUsers < item.userCount ? 600 : undefined,
+                  }"
+                >
+                  {{ item.acceptedUsers }} / {{ item.userCount }} 人
+                </td>
+              </tr>
+            </tbody>
+          </table>
+        </template>
+
+        <div class="foot">
+          <div class="foot-bar">
+            <div class="results">
+              <span
+                v-for="item in judgedResults"
+                :key="item.result"
+                :style="{
+                  width: percent(item.count, stats.total),
+                  background: resultColor(item.result),
+                }"
+              ></span>
+            </div>
+            <div class="legend">
+              <span v-for="item in judgedResults.slice(0, 5)" :key="item.result">
+                <i :style="{ background: resultColor(item.result) }"></i
+                >{{ resultName(item.result) }}
+                <b>{{ item.count }}</b>
+              </span>
+            </div>
+          </div>
+          <n-text depth="3" class="small foot-meta">
+            {{ languageText }} ·
+            {{ stats.flowchartCount ? `流程图 ${stats.flowchartCount} 张` : "流程图今天没人画" }}
+          </n-text>
+        </div>
       </template>
-    </template>
-    <!-- 请求失败时 stats 还是 null，转圈停下来总得留句话 -->
-    <n-empty v-else-if="!loading" description="统计拉取失败" style="margin: 40px 0" />
-    <div v-else style="height: 200px"></div>
-  </n-spin>
+
+      <!-- ==================== 学生：从简 ==================== -->
+      <template v-else>
+        <div v-if="meText" class="me">
+          <b>你今天</b>
+          <n-text depth="2">{{ meText }}</n-text>
+        </div>
+        <div class="numbers">
+          <div>
+            <b>{{ stats.total }}</b
+            ><span>次提交</span>
+          </div>
+          <div>
+            <b>{{ stats.userCount }}</b
+            ><span>人交了题</span>
+          </div>
+          <div>
+            <b>{{ Math.round(stats.correctRate) }}%</b><span>提交做对了</span>
+          </div>
+        </div>
+        <template v-if="stats.problems.length">
+          <b class="section-title">今天大家都在做</b>
+          <div class="rows">
+            <a
+              v-for="item in stats.problems"
+              :key="item.problemDisplayId"
+              href="#"
+              class="row"
+              @click.prevent="emit('openProblem', item.problemDisplayId)"
+            >
+              <span class="row-title">
+                <n-text depth="3">{{ item.problemDisplayId }}</n-text> {{ item.problemTitle }}
+              </span>
+              <n-text depth="3" class="small">
+                {{ item.userCount }} 人做 · {{ item.acceptedUsers }} 人对
+              </n-text>
+              <span v-if="item.mine === 'accepted'" class="mine done">
+                <Icon icon="ph:check-bold" :width="12" />做对了
+              </span>
+              <span v-else class="mine go">{{ item.mine === "tried" ? "接着做" : "去做" }} ›</span>
+            </a>
+          </div>
+        </template>
+      </template>
+    </div>
+  </div>
 </template>
 
 <style scoped>
-.stat-item {
+.today {
+  width: min(560px, calc(100vw - 32px));
+  max-height: 86vh;
   display: flex;
   flex-direction: column;
+  border-radius: 12px;
+  background: v-bind("theme.cardColor");
+  box-shadow: v-bind("theme.boxShadow3");
+  font-size: 14px;
+  overflow: hidden;
+}
+
+.today.wide {
+  width: min(880px, calc(100vw - 32px));
+}
+
+.head {
+  flex: none;
+  display: flex;
+  align-items: center;
+  gap: 10px;
+  padding: 16px 20px 14px 24px;
+  border-bottom: 1px solid v-bind("theme.dividerColor");
+}
+
+.title {
+  font-size: 18px;
+}
+
+.pill {
+  font-size: 12px;
+  padding: 1px 8px;
+  border-radius: 10px;
+  background: v-bind("theme.actionColor");
+  color: v-bind("theme.textColor2");
+}
+
+.spacer {
+  flex: 1 1 0;
+}
+
+.close {
+  width: 32px;
+  height: 32px;
+  border: 0;
+  border-radius: 4px;
+  background: transparent;
+  color: v-bind("theme.textColor2");
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  cursor: pointer;
+}
+
+.close:hover {
+  background: v-bind("theme.actionColor");
+}
+
+.body {
+  overflow: auto;
+  padding: 18px 24px 22px;
+  display: flex;
+  flex-direction: column;
+  gap: 14px;
+}
+
+.small {
+  font-size: 13px;
+}
+
+.tiny {
+  font-size: 12px;
+}
+
+.center {
+  display: flex;
+  justify-content: center;
+  padding: 40px 0;
+}
+
+.empty {
+  padding: 40px 16px;
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  gap: 8px;
+}
+
+.empty-icon {
+  width: 44px;
+  height: 44px;
+  border-radius: 50%;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  background: v-bind("theme.actionColor");
+  color: v-bind("theme.textColor2");
+}
+
+.numbers {
+  display: flex;
+  gap: 36px;
+  flex-wrap: wrap;
+}
+
+.numbers > div {
+  display: flex;
+  flex-direction: column;
+}
+
+.numbers b {
+  font-size: 26px;
+  line-height: 1.2;
+  font-variant-numeric: tabular-nums;
+}
+
+.numbers span {
+  font-size: 13px;
+  color: v-bind("theme.textColor3");
+}
+
+.live {
+  display: flex;
+  align-items: center;
+  padding: 10px 14px;
+  border-radius: 8px;
+}
+
+.live-link {
+  color: inherit;
+  font-weight: 600;
+  text-decoration: none;
+  display: inline-flex;
   align-items: center;
   gap: 4px;
 }
 
-.hours {
+.section-title {
   display: flex;
-  align-items: flex-end;
-  gap: 2px;
+  align-items: baseline;
+  gap: 10px;
 }
 
-.hour {
+.timeline {
+  display: flex;
+  flex-direction: column;
+}
+
+.lane {
+  display: flex;
+  min-height: 42px;
+  border-bottom: 1px solid v-bind("theme.dividerColor");
+}
+
+.lane.axis-row {
+  min-height: 24px;
+  border-bottom: 0;
+}
+
+.lane-label {
+  width: 150px;
+  flex: none;
+  display: flex;
+  flex-direction: column;
+  justify-content: center;
+}
+
+.lane-name {
+  font-weight: 600;
+  color: v-bind("theme.textColor1");
+  text-decoration: none;
+}
+
+.lane-name:hover {
+  color: v-bind("theme.primaryColor");
+}
+
+.lane-track {
+  position: relative;
   flex: 1;
-  display: flex;
-  flex-direction: column;
-  align-items: center;
-  gap: 4px;
 }
 
-.hour-bars {
-  height: 72px;
+.grid {
+  position: absolute;
+  top: 0;
+  bottom: 0;
+  width: 1px;
+  background: v-bind("theme.dividerColor");
+}
+
+.lane-bar {
+  position: absolute;
+  top: 50%;
+  height: 16px;
+  margin-top: -8px;
+  border-radius: 4px;
+}
+
+.lane-text {
+  position: absolute;
+  top: 50%;
+  transform: translateY(-50%);
+  font-size: 13px;
+  white-space: nowrap;
+  color: v-bind("theme.textColor2");
+}
+
+.now {
+  position: absolute;
+  top: -4px;
+  bottom: -4px;
+  width: 2px;
+  background: v-bind("theme.successColor");
+}
+
+.axis span {
+  position: absolute;
+  top: 4px;
+  transform: translateX(-50%);
+  font-size: 11px;
+  color: v-bind("theme.textColor3");
+}
+
+.axis .now-label {
+  top: 4px;
+  font-weight: 600;
+  color: v-bind("theme.successColor");
+  background: v-bind("theme.cardColor");
+  padding: 0 2px;
+}
+
+.hard {
   width: 100%;
+  border-collapse: collapse;
+  font-size: 13px;
+}
+
+.hard th {
+  text-align: left;
+  font-weight: normal;
+  color: v-bind("theme.textColor3");
+  padding: 4px 8px 6px 0;
+  border-bottom: 1px solid v-bind("theme.dividerColor");
+}
+
+.hard td {
+  padding: 8px 8px 8px 0;
+  border-bottom: 1px solid v-bind("theme.dividerColor");
+  white-space: nowrap;
+}
+
+.hard .right {
+  text-align: right;
+  padding-right: 0;
+}
+
+.hard-title a {
+  color: v-bind("theme.textColor1");
+  text-decoration: none;
+}
+
+.hard-title a:hover {
+  color: v-bind("theme.primaryColor");
+}
+
+.mini {
+  display: inline-flex;
+  width: 70px;
+  height: 8px;
+  border-radius: 2px;
+  overflow: hidden;
+  gap: 1px;
+  margin-right: 8px;
+  vertical-align: middle;
+}
+
+.foot {
   display: flex;
   align-items: flex-end;
-  cursor: default;
-  /* 每格一段，拼成整条横轴。「现在」那一格换主色，粗细不动 —— 变粗会让那一格的
-     柱子底比别人高 1px */
-  border-bottom: 2px solid;
+  gap: 24px;
+  flex-wrap: wrap;
 }
 
-.bar {
-  width: 100%;
-  border-radius: 2px 2px 0 0;
-  transition: height 0.2s;
+.foot-bar {
+  flex: 1;
+  min-width: 280px;
+  display: flex;
+  flex-direction: column;
+  gap: 8px;
 }
 
-.hour-label {
-  font-size: 11px;
-  line-height: 14px;
-  opacity: 0.6;
+.results {
+  display: flex;
+  height: 10px;
+  border-radius: 3px;
+  overflow: hidden;
+  gap: 1px;
+}
+
+.legend {
+  display: flex;
+  flex-wrap: wrap;
+  gap: 4px 14px;
+  font-size: 13px;
+  color: v-bind("theme.textColor2");
+}
+
+.legend i {
+  display: inline-block;
+  width: 9px;
+  height: 9px;
+  border-radius: 2px;
+  margin-right: 5px;
+}
+
+.me {
+  display: flex;
+  gap: 12px;
+  padding: 12px 16px;
+  border-radius: 8px;
+  background: v-bind("theme.actionColor");
 }
 
 .rows {
   display: flex;
   flex-direction: column;
-  gap: 8px;
 }
 
 .row {
   display: flex;
   align-items: center;
   gap: 12px;
+  padding: 9px 2px;
+  border-bottom: 1px solid v-bind("theme.dividerColor");
+  color: v-bind("theme.textColor1");
+  text-decoration: none;
 }
 
-.row-name {
-  width: 72px;
-  flex-shrink: 0;
-}
-
-.row-bar {
+.row-title {
   flex: 1;
-}
-
-.row-count {
-  flex-shrink: 0;
-  font-variant-numeric: tabular-nums;
-}
-
-.problem {
-  flex: 1;
-  justify-content: flex-start;
+  min-width: 0;
   overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
+.mine {
+  flex: none;
+  font-size: 13px;
+  font-weight: 600;
+  display: inline-flex;
+  align-items: center;
+  gap: 3px;
+}
+
+.mine.done {
+  color: v-bind("theme.successColor");
+}
+
+.mine.go {
+  color: v-bind("theme.primaryColor");
 }
 </style>
diff --git a/apps/web/src/oj/submission/list.vue b/apps/web/src/oj/submission/list.vue
index a9485ea..56b5aa6 100644
--- a/apps/web/src/oj/submission/list.vue
+++ b/apps/web/src/oj/submission/list.vue
@@ -1068,14 +1068,13 @@ function dayBreak(index: number) {
     </n-drawer-content>
   </n-drawer>
 
-  <n-modal
-    v-model:show="todayPanel"
-    preset="card"
-    :style="{ maxWidth: isDesktop && '700px', maxHeight: '80vh' }"
-    :content-style="{ overflow: 'auto' }"
-    title="今日提交统计"
-  >
-    <TodayStatistics @open-problem="(id: string) => openProblem({ problemDisplayId: id } as Row)" />
+  <!-- 标题栏在组件里：要写「截至几点」「判题中几条」，只有拉到数之后才知道 -->
+  <n-modal v-model:show="todayPanel">
+    <TodayStatistics
+      @close="todayPanel = false"
+      @loaded="(total: number) => (todayCount = total)"
+      @open-problem="(id: string) => openProblem({ problemDisplayId: id } as Row)"
+    />
   </n-modal>
 </template>
 
diff --git a/apps/web/src/utils/types.ts b/apps/web/src/utils/types.ts
index 7010a4a..a88105d 100644
--- a/apps/web/src/utils/types.ts
+++ b/apps/web/src/utils/types.ts
@@ -82,6 +82,7 @@ export type ProblemStatus = "passed" | "failed" | "not_test"
  */
 export type { Tag, TagCategory } from "@oj2/contract"
 export type { ProblemStats, ProblemClassDetail } from "@oj2/contract"
+export type { TodaySubmissionStatistics } from "@oj2/contract"
 
 export type {
   AdminTag,
diff --git a/packages/contract/src/submission.ts b/packages/contract/src/submission.ts
index 0532705..1e6c206 100644
--- a/packages/contract/src/submission.ts
+++ b/packages/contract/src/submission.ts
@@ -413,7 +413,16 @@ export const submissionStatisticsSchema = z.object({
  * 口径跟着那颗标签走：**东八区今天、非比赛提交、不分语言**（语言分布就是
  * `languages` 这张表本身）。
  */
+const todayFailureSchema = z.object({ result: judgeStatusSchema, count: z.number().int() })
+
+/**
+ * 「今日统计」（提交列表顶上那颗标签点开的）。一般是老师在看（设计稿「今日统计重设计」老师 B）：
+ * 今天哪几个班上了课、各在几点、错得最多的是哪几道。学生版从简：自己今天怎样、大家在做哪几道。
+ * 口径：东八区今天 + 非比赛提交。
+ */
 export const todaySubmissionStatisticsSchema = z.object({
+  /** 这份数据是几点算的 —— 标题上的「截至 19:40」 */
+  asOf: z.string(),
   total: z.number().int(),
   /** 通过的条数，含 AST_CHECK_FAILED（那也是答案对了） */
   accepted: z.number().int(),
@@ -425,24 +434,78 @@ export const todaySubmissionStatisticsSchema = z.object({
   correctRate: z.number(),
   /** 今天交过东西的人数，按 user_id 去重 */
   userCount: z.number().int(),
-  /** 按东八区钟点分的 24 个桶，**下标就是钟点**，没有提交的钟点是 0 */
-  hours: z.array(z.number().int()).length(24),
-  /** 按语言，提交数倒序。零提交的语言不在表里 */
+  /** 今天画了几张流程图，0 就不提 */
+  flowchartCount: z.number().int(),
+  /** 按语言，提交数倒序。只有一种语言时界面上缩成一句话 */
   languages: z.array(z.object({ language: problemLanguageSchema, count: z.number().int() })),
-  /** 按判题结果，条数倒序 */
-  results: z.array(z.object({ result: judgeStatusSchema, count: z.number().int() })),
+  /** 按判题结果，条数倒序 —— 画成底部那根结果条 */
+  results: z.array(todayFailureSchema),
+  /** 我今天交了几次、做对几道。没登录为 null */
+  me: z.object({ total: z.number().int(), solved: z.number().int() }).nullable(),
   /**
-   * 今天最热的几道题，提交数倒序，最多 10 道。
-   * **只含公开可见的题目** —— 这个接口不需要登录，不能拿它探未发布题目的标题。
+   * 学生版「今天大家都在做」：按做的人数倒序，最多 8 道。**只含公开可见的题目** ——
+   * 这个接口不需要登录，不能拿它探未发布题目的标题。「提交列表对学生全开」关掉时为空
    */
   problems: z.array(
     z.object({
       problemDisplayId: z.string(),
       problemTitle: z.string(),
-      count: z.number().int(),
-      acceptedCount: z.number().int(),
+      userCount: z.number().int(),
+      acceptedUsers: z.number().int(),
+      /** 我自己今天在这道题上：做对了 / 交了没对 / 没交；没登录为 null */
+      mine: z.enum(["accepted", "tried", "none"]).nullable(),
     }),
   ),
+  /**
+   * 老师：今天上了课的班（同班 5 人以上做了同一道题），按开始时间排。学生为 null。
+   * 时段是这个班今天第一条到最后一条提交，`live` = 最后一条在 15 分钟内（正在上课，
+   * 界面上引去课堂看板 —— 盯人是看板的活）
+   */
+  classes: z
+    .array(
+      z.object({
+        className: z.string(),
+        start: z.string(),
+        end: z.string(),
+        userCount: z.number().int(),
+        /** 班里的学生数 */
+        classSize: z.number().int(),
+        /** 这节课做的题数（班里 5 人以上做过的） */
+        problemCount: z.number().int(),
+        /** 多半是从题单里交的 —— 「题单 9 道」 */
+        fromProblemSet: z.boolean(),
+        total: z.number().int(),
+        correctRate: z.number(),
+        live: z.boolean(),
+      }),
+    )
+    .nullable(),
+  /** 老师：没上课的零星提交，按班（null = 没填班级的号） */
+  scattered: z
+    .array(
+      z.object({
+        className: z.string().nullable(),
+        userCount: z.number().int(),
+        total: z.number().int(),
+      }),
+    )
+    .nullable(),
+  /** 老师：错得最多的题，按没过的次数倒序，最多 6 道 */
+  hardProblems: z
+    .array(
+      z.object({
+        problemDisplayId: z.string(),
+        problemTitle: z.string(),
+        /** 这道题今天交得最多的那个班 */
+        className: z.string().nullable(),
+        total: z.number().int(),
+        accepted: z.number().int(),
+        failures: z.array(todayFailureSchema),
+        userCount: z.number().int(),
+        acceptedUsers: z.number().int(),
+      }),
+    )
+    .nullable(),
 })
 
 export const formatCodeRequestSchema = z.object({